The objective of this study was to determine the effect of thermocycling only on the tensile bond strengths of four orthodontic adhesives. With the advent of bonded orthodontic brackets, spontaneous bond failures have been a constant confounding phenomenon. Consequently, numerous studies have been published dealing with the 'bond strength' issue. The focus of these studies is varied, and range from the mode of tooth surface preparation, the type of adhesive, and the type of bracket base design used.

Other studies investigated the effects of different testing methods, such as the traditional shear/peel-type to impact testing. This study was designed to nullify some of these variables and isolate the effect of thermocycling on the bond strength of four commonly used orthodontic adhesives. The adhesives were Transbond XT (3M/Unitek, Monrovia, Calif), Fuji Ortho LC (GC America Corp, Alsip, 111), Phase 11 (Reliance Orthodontic Products Inc, Itasca, 111), and System 1+ (Ormco Corp, Glendora, Calif). Flat-based lingual button attachments (Ormco Corp, Glendora, Calif) were bonded to 240 prepared bovine incisors. Each adhesive group was subsequently divided into four sub-groups subjected to different regimens of thermocycling of 5 °± 3 ° C and 55 ° ± 2 ° C with 30-second dwell times. The first subgroup were not subjected to thermocycling and served as a comparison control, the three remaining subgroups were subjected to 1,000, 2,000, and 4,000 thermocycles.

Bond strength was then tested in tensile mode using an MTS universal testing machine, model 1125 (MTS System Corporation, Eden Prairie, Minn).

Statistical analysis using the Mann-Whitney U test, and the Kruskal-Wallis multiple comparison test showed that there were no significant differences in the bond strengths among the subgroups subjected to different treatment within the adhesive groups (α=0.05).

LLU Discipline

Orthodontics and Dentofacial Orthopedics




Graduate School

First Advisor

Carlos A. Munoz

Second Advisor

Craig A. Andreiko

Third Advisor

Joseph M. Caruso

Fourth Advisor

Neil P. Jessop

Fifth Advisor

Jay S. Kim

Degree Name

Master of Science (MS)

Degree Level


Year Degree Awarded


Date (Title Page)




Library of Congress/MESH Subject Headings

Tissue Adhesives; Dental Bonding -- methods



Page Count

viii; 32

Digital Format


Digital Publisher

Loma Linda University Libraries

Usage Rights

This title appears here courtesy of the author, who has granted Loma Linda University a limited, non-exclusive right to make this publication available to the public. The author retains all other copyrights.


Loma Linda University Electronic Theses and Dissertations

Collection Website



Loma Linda University. Del E. Webb Memorial Library. University Archives